Director firing system



H. c. FORD 1,840,497

DIRECTOR FIRING SYSTEM Filed Aug. 16. 1918 10 Sheets-Sheet 1 MINUTES GUN ELEVATION 20 "mp s I @1 O R UT 2/ I LE ELEVA r 0 .IIVDICA R 5 MPH Jan. 12, 1932. H. c. FORD 'DIRECTOR FIRING SYSTEM Filed Aug. 16. 1918 10 Sheets-Sheet 2 m VENTOR ,4 T7 OR BY Jan. 12, 1932. H. c. FORD DIRECTOR FIRING SYSTEM 10 Sheets-Sheet 3 Filed Aug. 16. 1918 11v VENT R z B y Y whlflw A T T ORN Y Jan. 12, 1932. H. c. FORD DIRECTOR FIRING SYSTEM Filed Aug. 16. 1918 1,0 SheetsSheet 4 QMN mkwm Jan 12, 1932. FORD 1,840,497

DIRECTOR FIRING SYSTEM Filed Aug. 16. 1918 10 Sheets-Sheet 5 A T TORNE INVENTOR Jan. 12, 1932. c; FORD 1,840,497

DIRECTOR FIRING SYSTEM Filed Aug. 16. 1918 10 Sheets-Sheet 6 (9/ 7% Flag 751 11v VENTOR Jan. 12, 1932. H F R 1,840,497

DIRECTOR FIRING SYSTEM Filed Aug. 16. 1918 10 sheets-sheet 7 INVENTOR v 42 (J- ;Z/2/

)4 TTORNE l0 Sheets-Sheet 8 H. C. FORD DIRECTOR FIRING SYSTEM Filed Aug. 16. 1918 Jan. 12, 1932.

INVENTOR yflww 6. m QQ WI H 772 A TTORNE Jan. 12, 1932. H. c. FORD 1,840,497

DIRECTOR FIRING SYSTEM Filed Aug. 16. 1918 10 Sheets-Sheet 9 11v VENTOR ATTORNEY Patented Jan. 12, 1932 wa es HANNIBAL C. FORD, OF JAMAICA, NEW YORK, ASSIGNOR '10 FORD INSTRUMENT (10., 1116;, OF NEW YORK, N. "2., A CORPORATION OF NEW YORK DIRECTOR FIRING SYSTmI Application filed August 18, 1918. Serial No. 250,228.

This invention relates to fire control systems or more particularly to a system for controlling the sighting of a. gun or guns of a battle-ship or other armored craft. The

.- zontal plane and it frequently occurs that it is desirable or necessary to fire the gun or guns when the ship is inclined to the horizontal. For this reason a. directorscope is used which measures the angle which the deck of the vessel makes with the horizontal plane when the shot is fired.

It is the purpose of the present invention to I provide a system in which the directorscope angle and the range converted into an angle J corrected angle transmitted to the gun so of gun elevation may be combined and the that the gun will throw a projectile the required range when it is fired with the vessel inclined to the horizontal.

Additional objects of the invention are to provide a system of this character which is flexible and which is not likely to be put out of action during a-naval engagement.

Still further objects and advantages of the system will be apparent from the detailed description hereinafter to follow when taken in conjunction with the accompanying drawings and which will be particularly pointed out in the appended claims.

In the drawings:

Fig. 1 shows somewhat diagrammatically one embodiment of the invention;

Fig. 2 is a plan of the range converter;

Fig. 3 is a plan of the dials for indicating the gun elevation or the directorscope angle in minutes of arc;

Fig. 4 is a view similar to Fig. 2 with the top plate removed to show the interior mechanism of the range converter;

Fig. 4a is a detail of the stop for the drumshifting plunger;

Fig. 5 is a section on the line 55 of Fig. 4, looking in the direction ofthe arrows;

Fig. 6 is a section on the line 66 of Fig. 7 shows the side elevation of the instrument, a portion of the casing being removed to more clearly show the parts.-

Fig. 8 is a section on the line 88 of Fig. 6;

Fig.9 is a section in the line 99 of Fig. 4

Fig. 10 is a sectionon the line 10-10 of Fig. 4;

ig. 11 is a detail showing a section, on the line 11.11 of Fig. 10;

Fig. 12 is a section on the line 1212 of Fi 7-' Fig. 13 is a plan of one of the differential gears; I

Fig. 14 is an end figure of the diiferential; Fig. 15 is a front View of the differential; Fig. 16 isla section on the line 16-16 ofFig. 4.1ooking in the direction of the arrows;

- F ig..17 is a'section on, the line 17-17 of Fig. 16 looking in the direction of the arrows Fig. 18 is, a-section of the directorscope transmitter on the line 1818'of Fig. 1;

Fig. 19 is a section on the line 1919 of Fi 18 looking in the direction of the arrows;

ig. 20 is a detail showing the dails .and transfer mechanism therebetween;

Fig. 21 is a front view of the gun elevation indicator with the top plate removed to more clearly show the parts; v

Fig. 22 is a section on the line 2222 of Fig. 21; Fig. 23 is a diagram of the electrical connections of the system, part of the mechanical instrumentalities being shown to fully identify the parts; and

Fig. 24 is a diagram showing the manner in which a plurality of transmitters and range converters are connected together.

Referring to Fig. 1, here a simplified form of one embodiment of the system is shown somewhat diagrammatically for the purpose of illustration, it being understood that the directorscope per se and gun elevating mechanism per se shown form no part of the invention. The directorscope shown is of a well known type and comprises a periscope 1 which is mounted in a support 2, the latter in turn, being mounted upon trunnions 2' carried by a sleeve 3 which is mounted upon a ring 4 secured to the conning-tower or other part of the vessel whichis indicated at 5. The sleeve 3 is free to rotate in the ring 4 upon ball bearings 6 so that the periscope may be swung on its vertical axis'to bear upon the target. The sleeve 3 carries a rigid arm 7 and the support 2 which surrounds the periscope carthereto.

ries downwardly diverging arms 11 and 12 which are secured togetheriat their ends by a rack 13, it being understood-that the rack andiperiscope 1 swing together through the same angle. Mounted upon the arm 7 is a small gear 14 which meshes with the rack 13. This gear is secured upon a shaft 15 which shaft carries a larger gear 15, also secured torscope angle transmitter 16 which is elec trically connected by' an electric cable 17 to a range converter18. The rang converter is connected to an electric cable 19 to a gun elevation indicator 20 which is connected to the gun. In the illustration shown, the gun is designated 21 and is mounted upon trunf nions'22. The gun may be elevated in any approved manner and in the construction shown, a motor 23 actuates the variable speed hydraulic gear 24 which is connected by that will be'hereinafter described in detail.

extends beyond the casing and carries a Referring now to the directorseope transmitter, the gear 14 which meshes with the rack 13, is mounted upon the support 7 for the periscop'e 1. To change the. angle of the periscope 1, the gear .14 is rotated which will.

shift the movable rack 13 until the'directorscope makes the desired angle'with the deck of the vessel, and the amount which the periscope is shifted from the vertical,-will give the director'scope angle, since this angle is equal to the angle which the deck of-the vessel will make with the horizontal. The shifting of the Periscope is accomplished through the gear 14 by the construction shown in Figs. 18, .19 and 20 of the drawings. Here the directorscope transmitter is shown in detail and comprises a casing 40 having a top plate 41. Passing through this closed casing is a shaft42 which carries a gear 14a. The other end of the shaft also The gear 14 is driven by a direc-- ilar number of divisions and knurled head 43 by means of which the gear 14a is rotated. When rotated, gear 14a drives gear 15 indicated in Fig. 1, thus turning the shaft 15 and the gear 14 mounted thereon,

which in turn, acts on rack 13 to actuate the periscope. Mounted within the casing 40 is an electrical transmitter for transmitting the angle of the directorscope. This transmitter is of a similar construction to that shown in my United States Letters Patent for an electrical transmitter, granted May 3, 1927, and numbered 1,627,16

1 The transmitter comprises a frame consist- "ing segments 47 and 48 is mounted upon a shaft 54 which is driven from the shaft 42 by means of gears 55 and 56. As best shown in dotted lines in Fig. 19, a lever 55 is pivoted to the wall of the casing and-carries at its lower end a roller 55* which is maintained in engagement with gear 55 by a spring 55 attached at one end to the removable lever and at the other to a pin extending from the easing. Thus, as the rotary contact switches are turned, the roller 55v snaps between the teeth of gear 55, and imparts a step-by-step rotation thereto. The rotary switch comprising contact segments 49 and 50 is mounted upon a shaft 57 which is driven through a transfer mechanism consisting of Geneva gears 58 and 59 and gears 60 and 61, the ratios between the gears being such that for a complete revolution of the-shaft. 54 the shaft 57 is driven a one-twentieth of a revolution. The shafts 54 and 57 carry dials 60 and 6l 'respe'ctively. The dial 60 is divided into twenty parts, the graduation being indicated by the numerals 00 to 95 and the dial 61 is divided into a simnumerals 0 to 19 inclusive. I

These dials are utilized to give the directorscope angle in minutes ofarc and for convenience one thousand minutes has been arbitrarilyselected to correspond to the periscope when the periscope' is directly perpendicular to the deck of the vessel, and readings below a thousand indicate that the directorscope is set to fire the guns when the deck of the vessel is inclined upwardly, with espect to the target, so that the directorscope angle must be subtracted from the angle of gun elevat-ion.

Readings above one thousand indicate that the directorscope is set at an angle at which the deck of the vessel is inclined downwardly, with respect to-the target, so that the directorscope angle must be added to the angle designated by of the gun elevation in order to correct the un elevation for the directorscope angle.

' For example: in the present construction a reading of 1225 minutes is indicated by the directorscope, which corresponds to the position of the dot and dash line and which indicates that the deck of the vessel at the moment that the shell is to be fired from the gun will be tilted downwardly an angle of 225 from the horizontal, which angle must be added to' the gun elevation in minutes (which in Fig. 1 is shown to be 465') to give the corrected gun elevation of 690'. By this construction directorscope angles of 1,000

minutes from from the horizontal in either direction may be obtained. I

Referring now to the transmission system which is utilized to transmit the directorscope angle to the range converter 18, this system comprises a step-by-step transmission system, the transmitter of which has been described as consisting of rotary switches having contacts 47, 48, 49 and which are surrounded by brushes 52 carried by postsv 51. In Fig. 23 the electrical system of transmission used is clearly shown. Here the rotary contacts 47 and 48 are each shown as consisting of a 'slip ring and contact segments numbered 47a and 48a, respectively, the rotary contacts 49 and 50 of a similar construction, having contact segments 49a and 50a. The current for the transmission system is supplied by line wires (B and 64 which connect to acut-out switch 65 and are connected by wires 66 and 67 to the plus and minus terminal bars which are also disclosed in F ig'.- 19. These terminal bars are connected by wires (not shown) to posts or screws 68 which are each electrically connected by spring clips 69 to one of the posts 51, it being understood that similar osts and spring clips are utilized to electrically connecteach of the terminal bars-ofwthe set shown in Fig. 19 and designated 1, 2,

. 3,4. 5, 6, 7, 8, 9 and 10. These spring clips are shown in Fig. 18 and in dotted lines in .Fig. 19. 7

Referring again to Fig. 23 it will be seen that the terminal bar is connected by a wire 70 to a brush 71 which engages the slip ring connected to the contact segment 50a and by a wire 72 to a brush 73 which engages the slip ring electrically connected at segment 47a so that contact segments 50a and 47 a are permanently energized with a curnated 1 to 5 inclusive are connected by wires to five brushes spaced equal distances around the contact segments 49a and 50a and the terminal bars designated 6 to 10 inclusive.

are electrically connected by wires to five similar brushes surrounding the contact segments 47 a and 48a, the arrangement of the brushes being the same as in my Patent No.v I

1,627,168 referred to above. The terminal bars and and 1 to 10 inclusive are connected by wires inthe cable 17 to the converter, the Wires from each of'the brushes passing to the poles of a step-by-step motor, Y

. which will be later described.

This range converter is clearly disclosed in Figs. 2 to 17 inclusive .of the drawings and consists of a casing having a bezel 81 and a glass cover plate 82 which, forms a closed casing for the mechanism of the converter. As before stated, the function ofthe range converter is to convert the readings of range into,angles of gun elevation and to correct.

the angle of gun elevation for the directorscope angle, and the mechanism for performing this function will now be described.

Secured to lugs extending from the inner walls of the casing are two supporting plates 83 and 84 which plates have secured to'them' side plates 85 and 86 which are held in spaced relation by tie rods 87. Mounted between the side plates 85 and 86 is a range drum 88 0011- si'sting of a hollow cylindrical body mounted upon-a hollow shaft 89 which is supported at its ends upon ball bearings 90 and 91. The drum is loosely mounted upon this hollow shaft and has alongitudinal movement therealong, as will be later referred to. to one end of the hollow shaft 89 (see Fig.

6) is a bushing 92 to which is fastened a gear 93 which gear is fixed against longitudinal movement but is secured to the range drum Secured by dowel pins 94 which slide in openings in one of the side walls of the range drum whereby the drum is free to move longitudinally:

with respect to the gear but is constrained to rotate with it. The range drum is driven by a crank 95 which is permanently mounted in a bearing in the side wall of the casing. The shaft of this crank carries a disk 96 provided with a slot into which fits a pin 97 carried. by a disk 98 mounted upon a shaft 99 to form a simple form of clutch between these parts. The shaft 99 is supported by the side plate 86 and an auxiliary side plate 100. The shaft '99 also carries a sleeve 101 upon which is formed a gear wheel .102 which meshes with a gear 102a that is also in mesh with the gear wheel 93 to drive the range drum when. the crank 95 is turned. 'The range drum carries two helically arranged rows of numerals which are spaced angular distances apart, proportionally to the gun elevations which they represent. To explain more fully, the angleto which a gun should be elevatedin order to throw a propeating the ciphers for each range reading;-

' nates a range of 13400 yards.

sov

jectile a required distance or range, is not directly proportional to the range, but requires greater changes in angular elevation at long ranges than at short ranges. In the present construction, one of these range scales is spaced angularly around the drum between each two ranges so that the angle is proportional to the required change in gun elevation for a corresponding range of a 14" gun having 2600 ft. seconds initial velocity. The other scale .is' spaced in accordance with the gun elevation required when firing under reduced charges or having 2000 ft.-seconds initial velocity. It is to be understood that by slightly varying the spacing of the range readings on the drum it may be used to indicate the angle required for any other type of gun.

The range drum is normally concealed by a top plate 103 which is supported from the plates 83 and 84 by posts 104. This top plate is provided with an elongated slot 105 (see Fig. 2) and supported upon a feed screw 106 is a shutter 107 which is provided with an openin gtherein through which one-of the numerals-on the drum is visible, this shutter being arranged behind the elongated slot 105. A ribbon 107 is connected at its ends to the shutter and conceals the portion of the drum which would otherwise be Visible through the slot 105. The feed screw 106 is driven by a gear 107a which meshes with a gear 107?) that is in mesh with the gear 93 carried by the range drum, so that as the range drum is rotated the shutter is moved longitudinally across the face of the drum to put the openin therein over the convolution of the helically arranged numerals upon the drum, so that range readings will appear behind the opening in the shutter.

For convenience two ciphers are placed upon the shutter to co-operate with thenumerals upon the drum in order to avoid refor example, the shutter is shown co-opcrating with the numeral 134 which desigmal position of the drum the shutter co-operat'es with the ranges designating full charges and'to indicate the reduced charges, the drum which is longitudinally movable upon the shaft 89, is displaced to bring the numerals of the convolutions of the other helical row of range readings beneath the opening in the shutter. This movement of the drum is accomplished by means of-a sliding plate 110 which, as is clear from Fig.

- 4 and Fig. 6 is provided with flanges 111 and 112 engaging the ends of the drum to cause the drum to be displaced with the plate. The. plate is held in its normal position by a spring 113, one end of which is carried by a post 114 secured to the plate 83 and the other end ofwhich is secured to the post 115 carried by the sliding plate 110, the post 114 passing In the northrough a slot in the plate 110. A pin 114. secured to plate 83 and passing through another slot in plate 110, cooperates with pin 114 in guiding plate 110 when the latter is caused to slide (see Fig.4a). When it is desired to use reduced charges, a knob 116 carried by a plunger 117 that is mounted in andpasses through the casing, is pressed 1nwardly, whereupon the'plunger 117 engages the end of the sliding plate 110 to move it and the ran e drum to the left, as. shown in Fig. 4 and I ig. 6, in which position the sliding plate may be locked against the tension of the spring 113 bymeans of a pin 118 on the plunger 117 which engages the end wall of a shelf 119" carried by the casing wall. A stop pin 120 may also be provided to prevent the pin 118 being inadvertently rotated I out of engagementwith the shelf 119'. Mounted upon the posts -115 and 115' (see Fig. '5) is a plate 121 which carrLeS the legends 142600 F. S. I. V., Full charge and .142000 F. S. I. V., Reduced charge,

which legends indicate that the two scales upon the drum are for 14" guns having 2600 and 2000 ft.-seconds initial velocity at full,

and reduced charges, respectively, (see Fig.

4). The top plate 103 is provided with an opening 122 behind which one of these legends appears, as will be clear from Figs 1 and 2, to indicate which range scale on the drum is co-operating with the shutter.

As before stated, the purpose of the unequal spacing of the range scale upon the range drum is for the purpose of converting the range into the angle of gun elevation. In

the embodiment of the invention shown. the converted raiige is indicated in minutes of are, as for example. from Fig. 1 it is evident that a range of 13,400 yards represents a gun elevation of 465 minutes for the particular gun for which the range scales upon the 'drum have been laid out. The manner in which the reading of gun elevation is obtained will now be described. Mounted upon the sleeve 10.1

which carries the gear 102 which drives the range drum, is a spiral gear 124 which spiral gear meshes with a corresponding gear 125 mounted upon a shaft 126. The shaft 126 is mounted between the supporting plate 84 and an auxiliary supporting plate 127. The shaft 126 also carries a dial 128 which is connected to a shaft 129 by a transfer mechan sm 130, the shaft 129 carrying a second dial 131. The construction of this transfer mocha-- scribed will be clear from the previous description but will be briefly referred to at this point to make the remaining description clear. When the full charge scale is being utilized theknob 116 is left in its normal position and the crank 95 is turned until the range corresponding to the range to which the gun is to be sighted, appears behind the opening-in the shutter 107, it being evident that upon rotation of the crank and range drum the shutter 107 is fed by the screw 106 to maintain it in alinement with the numerals of the helical range scale. When the range 7 corresponding to the range for which the gun is to be elevated appears behind the shutter, the corresponding gun elevation in minutes of arc is read from the dials 128 and 131 behind an-opening 137 in the top plate 103, as will be clear from Figs. 1' and It is evident that by converting the range into ininutes of arc for-a corresponding gun elevation, the angle of the directorscope may beadded or subtracted from thegun elevation to obtain the corrected gun elevation at which the gun should be sighted fora known range to correct for firing the gun when the vessel is inclined to'the horizontal.

The construction for performing this addition or subtraction will now be described. As before stated, the directors'cope angle is transmitted by means of the transmitter shown in Figs. 18, 19 and 20 of the drawings, to the range converter, the diagram of the electrical'transmitter and its wiring connection to the range converter being shown in Fig. 23 of the drawings. This transmitter, as has been described, consists of two rotary switches, each of which is surrounded by five independent brushes which lead'to'the ter-'- minals designated 1 to 5 and 6 to 10 of the range converter, (see Fig. 23). This transmitter and wiring form a part of an electrical step-by-step transmission in -which two step-by-step. motors are utilized of a similar construction to that shown in my United States Letters Patent for a signal system granted June 20. 1922, and numbered 1.420.030.

Briefly stated, one of the step-by-step inotors' consists of five poles designated 1a, 2a. 3a. 4a and 5a and the other one of five poles designated 60, 7a, 8a, 9a and 10a, each of which poles is surrounded by two coils connected in series, which are connected by wires 15, 25, etc., to the corresponding terminals, as shown in Fig. 23 of the drawings. Each of the five pole motors is provided with a polarized armature also having two coils connected in series, which coils are connected to the plus and minus terminals by wires 140 and 141, the coils of the two armatures being in parallel. The armature itself which is surrounded by these coils is provided with two segmental-shaped pole pieces, these segmental-shaped pieces of one motor being designated 143 and 144 and the segmentalshaped pieces of the other motor being designated 145 and 146. These motors are of the same construction as that disclosed in my copending application for signal system before referred to, and provides a step-by-step signal system which is self-synchronizing and which gives twenty steps for a five pole motor. The self-synchronizing feature of the system will be clear, if it is considered that the brushes of the transmitter are connected to individual poles of the step-by-step motor and the armatures 143, 144, 145 and 146 of the motors are polarized which will insure that the armature will always be rotated in accordance with the energizations of the poles.

The mechanical construction of the terminals designated 1, 2, 3, 4, 5, and 10, 9, 8, 7 and 6' of the range converter, is clearly shown in Figs. 6 andv 8. Each of the ter minals, as for example the terminal 1, consists of a spring clip fastenedto an insulated plate 150 which is mounted inthe casing of the range converter upon posts 151. These spring clips engage terminals 152 mounted upon an insulated plate 154 which supports the step-by-step motors, the terminals 152 being connected to the coils of the poles of the motor, as indicated in Fig. 23. It will also be clear from Fig. 6 that the poles of the motors are rigidly united by plates 156 and 157 and the two motors connected together by a tie plate 157 The armature shaft which carries the armatures. 143 and 144 is designated 158 and carries a small head 159. The arlnature shaft 158-- which carries the armatures 145 and 146 is provided with a similar head designated 160. These heads extend to the openings in the top plate 103 and are provided with arrowsas is indicated in Figs. '1 and 2 of the drawings. The shafts 158 and 158 alsoc'arry dials 161 and 162 which dials 4 are of the same construction as the dials shown-in Fig.3 of the drawing. The nu merals on these dials appear behind an opening 165 in the top plate 103 (see Figs. 1 and tion, each set of dials reads 1225' which in- 172 and 173 respectively. These shafts are 2' respectively, together with the upright plates mounted between upper and lower plates 175 and 175a respectively, which are Joined by vertically disposed plates 1756. Shafts 172 and 173 are also connected by a transfer mechanism 174 which is such that each time the dial 171 makes a complete revolution, the

dial 170 makes a one-twentieth of a revolution. Upper and lower plates 175 and 175a or posts-175b, form a frame that not only supports vertical shafts 172 and 173 and their interconnecting transfer mechanism 174, but also affords a support. for a shaft 182, the vertical plates 17 5?) serving as bearings therefor. The frame formed by plate 175 and associated parts is. removable independently -of plate 84 but normally is secured thereto by a small plate 177 (see Fig. 4) and is mounted upon lugs 176' in the-casing. The

shaft 173 carries a spiral gear 180- which meshes with a second spiral gear 181 mounted upon a" shaft 182. The shaft 182 is rotated b means of a crank 183 mounted upon the s aft 184 which is connected to the sh'aft182 bymeans of a clutch consisting of two disks 185 and 186 which are united by a pin and slot connection, similar to the disks 96 and 98 so that the plate 175 and dials 170 and 171,

etc., may be removed without disturbing the handle 183. The dials 170 and 171 in the operation of the device, are turned until the same numerals on the dials 170 and 171 appear behind the opening 182, as appear on the dials 161 and 162 behind the openmg 165, which latter dials, as described, are actuated by the step-by-ste receiver motors.

To aid in sync ronizing the readings of the two dials, a follow-the-pointer indicator is preferably used. This indicator consists of the heads 159 and 160 carried by the armature shafts of the receiver motors and rings 159a and 160a surrounding these heads. As shown in Figs. 16 and 17 of the drawings, the ring 160a is formed with a bushing 187 that is rotatable in an opening in the top plate 103. The bushing 187 is secured to a gear 188 which meshes with an intermediate gear 189 which, in turn, meshes with a gear 190 having a pin 191 fitting into a slot in the dial 171. The heads 159 and 160 are displaced angularly a similar amount to the dials 161 and 162 and when the crank 183 is turned to cause the reading before the in Figs. 13, 14 and 15.

opening 182' to correspond with the reading before the opening 165, the rings 159a an 160a will also be rotated and when the same reading appears before both openings, the arrows carried by the heads 159 and 160 will appear opposite the arrows carried by the rings 159a and 160a which will indicate that the readings of both dials are identical. In practice it has been found more convenient to follow two pointers of this character than to compare the two separate readings, althoughit is evident that this follow-thepointer indicator. is not essential to the operation of the system. I

As before stated, the dials 170 and 171 are spiral ears 180 and 181. It is therefore evident t at the angular displacement of the two shafts is added or subtracted,a resultant angular displacement will be obtained which is proportional to the corrected gun elevation. This is accomplished by means of the construction shown in Fig. 7 of the drawings. The shaft 182 is connected by means of two disks 182a and 190a having a pin and slot connection between them, to a shaft 190. This shaft carries a gear 191 and the shaft 99 carries a similar gear 192. The gears 191 and 192 mesh with gears 193 and 194, respectively. The gears 193 and 194 are loosely. mounted upon a shaft 195 and form a part of a differential gear which is shown clearly The center of the differential comprises a spider 196 which is fastened to the shaft 195. This spider carries two sets of pinions, one set being indicated197 and 198 and the other set being indicated 199 and 200. The pinion 199 meshes withthe gear 193, the pinion 200 with the gear 194; the pinions 199 and 200 are in mesh with each other. Similarly, pinions 197 and 198 are in mesh with each other, pinion 197 also meshing with gear 194 and pinion 198 with gear 193. These gears form a spur differential of a well known type so that the center of the differential will be displaced an amount which is proportional to the sum or difference of the angular displacements of the gears 193 and 194, depending upon whether the angular displacements of the gears 193 and 194 are in the opposite or in the same direction. The differential gear, will, therefore, add or subtract the angular displacements of shafts 182 and 99, or in other wordswill. add or subtract the directorscope angle and the angle of gun elevation and the center of the differential may theremounted upon the shaft 195, drives a gear 203 which is fastened to the shaft. This gear meshes with a gear 204 upon a sleeve 205 which is loosely mounted upon the shaft 190. The sleeve 205 also carries a spiral gear 206 which meshes with a spiral gear 20? upon a shaft 208, which shaft carries a dial 209 and is connected by a transfer mechanism 210 to a shaft 211 which carries a dial 212, the dials 209 and 212 being similar to the dials shown in Fig. 3 of the drawings, and since they are driven from the center of the differential, it is evident that numerals appearing before the opening 206a in' the top plate (shown in Figs. 1 and 2), will indicate the corrected gun elevation in minutes of are, which should be transmitted to the gun.

The system thus far described is capable of being utilized as a unit without the other features of construction to be hereinafter described, it being evident that the corrected gun elevation in minutes of are appearing before the opening 206a, may be transmitted to the gun in order to set the same in any desired manner, as for example, by telephone or any other type of signal transmission system.

In practice, however, it is desirable to con-' nect the range converter by a step-by-step electrical transmission system, to 'the gun and in Fig. 7 the shaft 195 is shown provided with a crown gear 215 which drives a. gear 216 of a transmitter 217, which is of the same construction as the transmitter shown in Fig. 18 which has already been described. This transmitter is electrically connected, as shown in the wiring diagram in Fig. 23, to the gun elevation indicator.

The gun elevation indicator is shown in Figs. 21 and 22 and consists of a casing 220 provided with a cover plate 221 having a sight opening 222-therein. Mounted within the casing is a pair of receiver motors 223 and 224, which are of the same construction as the receiver motors in the range converter 7 and in my co-pending application for signal.

' the drawngs as being mounted upon a shaft system No. 1,420,030, before referred to.

These receivermotors, 223 and 224 are mounted on a plate 224 of insulating material which is secured to lugs in ,the casing. The electrical connections to the coils of the receiver motors are made through spring clips 225 which engage terminal posts 226 receiver motors are provided with heads 227 and 228 which form a part of a follow-thepointe'r indicator, similar to 'the one previously described. These heads project through openingsin a top plate 229 and the top plate 229 is supported at one end by posts 230 secured'to a tie plate 230 that connects the frames of the receiver motors and at the other-end by posts 231 mounted upon a'frame 232 which also is securedto carries the head 228 is designated 233 and the shaft which carries the head 227 is identified by numeral 234 (see also Fig. 23). These shafts carry dials 235 and 236 respectively,whi ch are arranged in over-lapping relation. as shown in Fig. 21. The dial 235 is provided with two annular scales, one running from 00 to 47 in 2% minute steps and the inner row running from 50 to 97 'in half minute steps. The other dial, namely 236, is provided with two annular rows of openings and the dials are disposed in such a relation that the opening of the outer row of holes will be brought over the indications of the inner scale upon the dial 235, while the inner row of holes will come into alimement with the outer scale on the dial 235.-

Each annular row of;holes is also supplied -with a scale running from 0 to 9. When,

therefore, the dial 235 is vrotated for the first rotation of the dial, the outer scale will co-operate with one of the holesin dial 236 to give readings from 0 to47 and then the dial 236 will make a one-twentieth of a revolution to bring the hole of the outer row into position where the numerals 50 to 97 will appear successively behind the hole. In this manner readings of 2% minute steps each may be obtained from 0 to 997 which will elevation of the gun is indicated, by a second set of dials to enable the gun pointer to determine when the gun has been properly set: As before stated, the gun is provided with a rack 30 which drives, through intermediate gears, the pinion 35 of the gun elevation indicator. This pinion-is shown in Fig; 22 of 240, which shaft carries a Worm 241' which meshes with a worm wheel 242 mounted upon a stud shaft 243. Mounted in the frame 232 is a shaft- 244 having afiixed thereto a disk 244 which is connected by a pill 245 to the gear 242. The shaft 244 carries a'di'al 246 which is similar to the dial 235 and is connected by a transfer mechanism 247 to a shaft 248 which vcarries a dial 249, similar to the dial 236. \Vhen the gun is elevated by the-control mechanism showif the amount of angular elevation of the gun will be indicated by the two dials 246 and 249, which are read behind an opening 250, it being evident thatwhen the reading appearing before the opening 250 corresponds to the reading appearing before the opening 222, the gun has been properly sighted.

20 a disk 18211 results in therotation of disk 190a In .order to expedite the pointing ofthe gun, a follow-the-pointe1" system is preferably utilized which is in all respects simi Y pointed without necessitating the comparing of the readings upon the dials.

Referring again to the range converter, it will-be noted that, when crank 183 is 1'0- tated, the consequent turningof shaft 182 and that has a pin and slot connection with the disk 182a. As shown in Fig. 10, the pentagonal' disk 190a constitutes, in effect, a fivetooth ratchet wheel, which co-acts with roller 190b carried by lever 1900 that is pivoted to side plate 85. A spring 190d attached at one end to a pin projecting from plate and at the other end to lever 1900, keeps the roller 1901) carried by that lever in engagement with disk 190a. Y 'As this disk is rotated, it in turn rotates shaft 190 in steps of of a revolution, which, as will be explained, causes the transmitter 217 to transmit to the gun elevation instrument 20, shown'in Figs. 21 and 22, in such manner that this instrument will give gun elevation readings varyin by five minutes of are. This is evident, since, as eachstep of disk 190a represents a five-minute'of arc step, the 2: 1 ratio ofgear 191 on shaft 190 to gear 193 of the differential raises the rate of transmission to 10 minutes, the center of the differential comprising pinions 197 to 200, inclusive and spider 196 rotating at half the speed of gear 193, then restoring the transmission rate to 5 minutes. This is carried to transmitter 217 by shaft 195 to which spider 196 is screwed and by crown gear 215 meshing with the transmittergear 216.

Reference to the disks of the gun elevation instrument, as illustrated in Fig. 21, shows that the dials are angularly divided into twenty sub-divisions and that dials 235 and 246 give gun elevation readings from 00 to 97 i. e.. a total of 100 minutes. This number of minutes divided by the twenty sub-divisions referrcd to. gives the five minute steps which the just described transmission from crank 183 of the range converter has been shown to be arranged to give.

But it will also be observed that dials 235' and 246 are arranged to give readings in other.

by the gun pointer and not from the range converter. Dial 235 gives changes in gun elevation in steps of 2 degrees when handle of the range converter is operated. As disk 98, which is a ten-tooth ratchet wheel, is turned, the shaft 99 is rotated of a revolution, which corresponds to a change of gun elevation reading amounting to 2% min? utes. The gear 192 drives gear 194 of the difl'erentia'l and as the gear ratio is 2: 1 the rate of transmission is raised to 5 minutes.

This rate is again reduced to 2% minutes, since the center of the differential, as reviously set forth, rotates at half the spec of gear 194 under these conditions. As before stated, the transmission drive to transmitter 217, is, by shaft 195, crown gear 215 and transmitter gear 216, but as shown, in steps giving 2% minutes ofarc, changes in gun elevation reading. Y

The operation of the system will be clear from the previous description but will now be briefly referred to. The handle 43 of the directorscope transmitter 16 is first turned to set the periscope 1 at the desired angle to the deck of the ship corresponding to the angle to the horizontal at which it is desired to fire the gun. The actuation of the handle 43 not only actuates the periscope 1 but also actuates the electrical transmitter which has been described in detail and which energizes then operated by turning the handle 95 until the range rea ing appearing behind the shutter 107 corresponds to the range for which the guns are to be sighted, which will convert the range reading into a corresponding angle of gun elevation readable in minutes of arc, which may be read behind the opening 137 in the converter. The handle or crank 183 isalso actuated to synchronize the readingsof the dials behind the openings 165 and 182'. In this operation the followthe-pointer system consisting .of'.

heads 159 and 160 and rings 159a and 160a with the arrows carried by these parts may be utilized instead of comparing the-readings upon the dials as has been described.

The rings 159a and 160a should be rotated until the arrows are again opposite each The differential gearing within the converter will then' add or subtract these two readings and give the corrected gun elevation to send to the gun. The corrected gun elevation is electrically transmitted to the gun elevation indicator by means of the stepby-step transmission system described. The gym; pointer then actuates the variable speed hydraulic gearing and sets the gun so that the two readings of gun elevation appearing before the openings in the gun elevation indicator are the same. In this construction the follow-the-pointer head and ring are preferably utilized to expedite the setting of the gun.

Referring now to Fig. 24 of the drawings, a schematic arrangement for a battleship is shown which may be utilized in practice. Here a plurality of transmitters is shown which are indicated 265, 266, 267, 268 and 269. These transmitters are designated by proper legends indicating. the positions of the indepedent directorscopes on' the battleship. A plurality of range converters are also shown, which are indicated 270 and 271. The cables running from the respective transmitters instead of being directly connected tothe range converter as shown in Fig. 1, pass to a control switch 27 2, the transmitter 265 being connected to this control switch by a cable 273; the transmitter 266 by a cable 274; the transmitter 267 by a cable 275; the transmitter 268 by a cable 276 and the transmitter 269 by a cable 277. The control switch 272 is connected to the range converter 271 by a cable 278, it being understood that by operating the handle 279 of thecontrol switch any one of the transmitters may be directly connected to the range converter the type of control switch suitable for this purpose being disclosed in my United States Letters Patent granted June 12, 1923 and numbered 1,458,284. The circuit controller or control switch 272 is c'onnected to the line wires 63 and 64 by a cable 280. 'A second control switch 281 may also be utilized and cables 282 and 283 connect corresponding contacts within these control switches in parallel. This circuit controller 281 is connected by a cable 284 to the range converter 270. The control switch 281 is also connected to the line wires 63 and 64 by a cable 285.

Since the contacts in-the control switches are connected in parallel, it is evident that if desired, any one of the transmitters may be connected to one of the control switches and the other control switch thrown to its oif or disconnected position. If desired, however, one of the transmitters may be connected to one control switch and its respective range converter and any one of the other transmitters connected to the other control switch and its converter. In this mannera flexible system of fire control is obtained which will permit of divided firing, that is, permit the fire of the guns to be directed at two different targets, or one of the control switches and corresponding range converter may be thrown out of action by. disconnecting and connecting the control switch and the single converter used with any one of the directorscopes.

It is obvious that the invention as defined in the appended claims may be otherwise em bodied than in the specific form disclosed herein. For instance, while the quantities which are referred to are shown as elevation factors measured in a vertical plane of reference the invention is of course equally applicable to quantities in other than a. vertical plane and it is equally. obvious that other remote from the directorscope, means at said station for converting range into an angle of gun elevation, and means for adding the directorscope angle to the angle of eleva tion orfor subtracting it there rom, and means for transmitting the sum or difference of said an les'to a distant gun.

3. In a fire control system, means for transmitting the directorsco'pe angle to a remote station, a device at said station for measuring the director-scope angle having a part whose displacement is proportional to the directorscopeangle, a device at said station.

for converting range into gun elevation, having a part whose displacement is proportional to the angle of gun elevation for a given range and connections between said Y parts for adding the displacement of said first named part to said second named part,- or for'subtracting it therefrom.

'4. In a fire control system, means for transmitting, the directorscope angle to a; remote station, a device at said station for measuring the directorscope angle, having a part whose displacement is proportional to the directorscope angle, a device at said station for converting range into. gun elevation, having -apart whose displacement is proportional to the angle of gun elevation for a given range,

and differential gearing between said parts for adding the displacement of said first named part to said second named part or for subtracting it therefrom.

5. In a fire control system, means for transmitting the directorscope angle to a remote station, a device at said station for measuring the directorscope angle, having a part Whose displacement is proportional to the directorscope angle, a device at said station for converting range into gun elevation, having a part whose displacement is proportional to the angle of gun elevation for a given range, and differential gearing between said, parts for adding the displacement of said first named part tosaid second named part,

displacement is proportional to the directorscope angle, a device at said station for converting range into gun elevation, having a part whose displacement is proportional to the angle of gun elevation for a given range, and differential gearing between said. parts for adding the displacement of said first named part to said second named part, or for subtracting it therefrom, and means for indicating the sum or difference of said angular displacements in terms of gun elevation, and means for transmitting said 'last named gun elevatlon to a gun.

7. In a fire control system, an instrument for determining the sum or difference of the gun elevation and the directorscope angle, a plurality of directorscopes and an electrical transmission connecting any one of said directorscopes to said instrument.

8. In a fire control system, an instrument for determining the sum or difference of the angle of gun elevation corresponding to a given range and the directorscope angle, a plurality of directorscopes, and electrical means for connecting any one of said directorscopes to said instrument.

9. In a fire control system, an instrument for determining the sum or difference of the angle of gun elevation corresponding to a given range and the directorscope angle, a

-plurality of directorscopes and means for electrically connecting any one of said directorscopes to said instrument.

10. In a fire control system, a plurality of independent directorscopes, a pair of electrical transmitters having transfer mechanism therebetween and operatively connected to each directorscope for transmitting the angle of the directorscope, a pair of selfsynchronizing receiver motors at a station remote from the directorscope, means for selectively connecting the receiver motors to the transmitters and the directorscopes connected thereto and indicating devices associated with the motors for showing the angle of the directorscope to which the motors are connected.

11. In a fire control system, a plurality of instruments for combining the gun elevation corresponding to a given range and the directorscope angle, a plurality of directorscopes and means for electrically connecting any one of said directorscopes to any one of said instruments.

1 12. In a fire control system, a pluralitv of instruments for combining the gun elevation corresponding to a given range and the didials having transfer mechanism therebetween, an electrical transmitter operatively associated with each of the dials, a pair of self-synchronizing receiver motors, means for selectively connecting the receiver motors 'to the pairs of transmitters of the several directorscopes and dials actuated by the receiver motor for repeating the readingof the dials at the directorscope to which the motors are connected.

14. In a fire control system, m-eans for converting range into an angle of gun elevation having a part movable proportional to the angle of gun elevation, means for displacing a second part proportional to the angle of the directorscope and means for determining the sum or difference of said displacements, and means for indicating the sum or difference in terms of an angle of gun elevation.

15. In a fire control system, an instrumen comprising a movable range scale graduated variably'in proportion to the angles of gun elevation, means for displacing said scale having a part whose displacement is proportional to the angle of'gun elevation, a second part having. a displacement proportional to a directorscope angle and means for determining the sum or diiference of the displacements of said parts.

16. In a fire control system, a range drum having a spirally arranged scale thereon graduated proportional to corresponding angles of gun elevation, means for rotating said drum, means for indicating successive range readings of said range scale'when said drum ,is rotated, a part connected to said drum having a displacementproportional to the displacement of said drum, a second part adapted to be connect-ed to a directorscope having a displacement proportional to the directorscope angle and means for determining the sum or difference of the displacement of said parts.

17. In a fire control system, a range drum having a spirally arranged range scale thereon graduated proportionally to corresponding angles of gun elevation, means for rotating said drum, means for indicating successive range readings on said drum when rotated, a part connected to said drum having a displacement proportional to the displacement of said drum, a second part, means for displacing said second part proportional to a factor affecting the angle of gun elevation and means for determining the sum or difference of said angular displacements. 

